I found reference to VMwares OVFTool at http://blog.hviidnet.com/?p=134 and was interested because of my testing with Avamar VMDK backups. The Avamar process uses a VM that is deployed as an OVA file to proxy the VMDK backups. If multiple backups/restores are needed, you can simply spin up more proxies.
Below is an example that I used to deploy images.
ovftool -nw=”myNetwork” -n=”NewVMName” -ds=”DatastoreName” -vf=”Folder/Folder/Folder” “d:tempAvamarVmImageProxy-linux-5.0.101-32.ova” “vi://username:password@VirtualCenter/Datacenter/host/ClusterName”